Game trainers are programs made to modify memory of a computer game thereby modifying its behavior using addresses and values, in order to allow cheating. It can "freeze" a memory address disallowing the game from lowering or changing the information stored at that memory address (e.g. health meter, ammo counter, etc.) or manipulate the data at the memory addresses specified to suit the needs of the person cheating at the game.

Cheat codes are usually activated by typing secret passwords or pressing controller buttons in a certain sequence.[10] Some games may also offer a debug console that can be used to edit game parameters. Effects might include unlocking a character or improving a character's performance: for example providing a car with greater acceleration,[10] entering god mode or noclip mode, or visual gags with no practical purpose.